1. Field of the Invention
This invention relates generally to a closure assembly for a container, and more particularly, to such an assembly having a cap and a breakaway tamper evident membrane formed with the cap.
2. Description of the Prior Art
Closures or caps for containers typically are of the threaded screw or snap type construction and are utilized to seal the mouth of the container in either a resealable or non-resealable manner. In order to provide an indication to a consumer that the closure has been tampered with and the product within the container possibly tainted, various types of tamper evident members have been utilized in conjunction with such closures.
One type of tamper evident member for a container closure includes a removable plastic or metal band which is positioned about the periphery of the closure after it is affixed to the container, and typically spans the interstice between the closure and the container. Examples of such closures and bands are shown in U.S. Pat. Nos. 4,784,279 and 4,830,208. The bands of the type shown in such patents, however, typically are crimped, stretch fit or heat shrunk in place in an additional operation separate from affixing the closure to the container, and can be quite difficult to remove.
Closures also have been designed with an integrally formed tamper evident band extending therefrom. Such closures and bands, an example of which is shown in U.S. Pat. No. 4,106,653, typically are force fit over the mouth of the container and include a pull tab which can be grasped and pulled by a user to remove the band from the closure to enable removal of the closure from the container. Such pull tabs typically lie flat against the container and can be difficult to grasp. Furthermore, they provide an undesirable discontinuity in the shape of the closure and container which is not aesthetically pleasing and can provide packaging problems due to their odd shapes. Such pull tabs are not designed to extend outwardly from the closure and the container, because outward extension would subject the tabs to possible breakage during installation, shipping and handling.
It therefore is desirable to provide a closure assembly for a container having an end cap which includes a breakaway tamper evident membrane or band formed integrally therewith and in which the membrane includes a push release tab that, upon being pressed, releases outwardly from the closure assembly to enable the tab to be grasped and pulled by a user for removal of the remaining portion of the membrane. It also is desirable to provide such a closure assembly which, in its assembled position on the container, provides a continuous aesthetically pleasing profile and which is easy to install and closely resembles conventional end closures that do not include any type of tamper-evident membranes or bands.